1
|
Evsiukova VS, Arefieva AB, Sorokin IE, Kulikov AV. Age-Related Alterations in the Level and Metabolism of Serotonin in the Brain of Males and Females of Annual Turquoise Killifish ( Nothobranchius furzeri). Int J Mol Sci 2023; 24:ijms24043185. [PMID: 36834593 PMCID: PMC9959878 DOI: 10.3390/ijms24043185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/03/2023] [Accepted: 02/03/2023] [Indexed: 02/08/2023] Open
Abstract
The annual turquoise killifish (Nothobranchius furzeri) is a laboratory model organism for neuroscience of aging. In the present study, we investigated for the first time the levels of serotonin and its main metabolite, 5-hydroxyindoleacetic acid, as well as the activities of the key enzymes of its synthesis, tryptophan hydroxylases, and degradation, monoamine oxidase, in the brains of 2-, 4- and 7-month-old male and female N. furzeri. The marked effect of age on the body mass and the level of serotonin, as well as the activities of tryptophan hydroxylases and monoamine oxidase in the brain of killifish were revealed. The level of serotonin decreased in the brain of 7-month-old males and females compared with 2-month-old ones. A significant decrease in the tryptophan hydroxylase activity and an increase in the monoamine oxidase activity in the brain of 7-month-old females compared to 2-month-old females was shown. These findings agree with the age-related alterations in expression of the genes encoding tryptophan hydroxylases and monoamine oxidase. N. furzeri is a suitable model with which to study the fundamental problems of age-related changes of the serotonin system in the brain.
Collapse
Affiliation(s)
- Valentina S. Evsiukova
- Department of Psychoneuropharmacology, Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alla B. Arefieva
- Department of Genetic Collections of Neural Disorders, Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Ivan E. Sorokin
- Department of Monogenic Forms of Human Common Disorders, Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Alexander V. Kulikov
- Department of Genetic Collections of Neural Disorders, Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia
- Correspondence: ; Tel.: +7-3833636187
| |
Collapse
|
2
|
Peters TMA, Lammerts van Bueren I, Geurtz BP, Coene KLM, de Leeuw N, Brunner HG, Jónsson JJ, Willemsen MAAP, Wevers RA, Verbeek MM. Monoamine oxidase A activity in fibroblasts as a functional confirmation of MAOA variants. JIMD Rep 2021; 58:114-121. [PMID: 33728254 PMCID: PMC7932864 DOI: 10.1002/jmd2.12194] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 12/15/2020] [Indexed: 11/07/2022] Open
Abstract
AbstractMonoamine oxidase A (MAO‐A) deficiency is a rare inborn error of metabolism with impaired degradation of biogenic amines including 5‐hydroxytryptamine (5‐HT), resulting in borderline intellectual disability and behavioral abnormalities. Genetic variants in MAOA need functional confirmation to enable a definite diagnosis. To this end, we developed an inexpensive, simple and nonradioactive MAO‐A activity assay based on the conversion of 5‐HT into 5‐hydroxyindoleacetic acid (5‐HIAA). Fibroblast cell lysates were incubated with 5‐HT and aldehyde dehydrogenase to allow 5‐HIAA production. 5‐HIAA was quantified using high‐performance liquid chromatography with fluorimetric detection. We optimized reaction mixture components, pH, and substrate concentration and tested linearity and specificity of the assay. We verified the functional validity of the enzyme assay using fibroblasts of controls, female mutation carriers and MAO‐A deficient patients. This included a newly described patient with a novel MAOA variant (c.1336G>A, p.(Glu446Lys)), who represents the fifth MAO‐A deficiency family so far. The optimized enzyme assay showed good linearity and specificity. Application to clinical samples showed a 100% differentiation of affected patients (with negligible MAO‐A enzyme activity) and controls or mutation carriers. In conclusion, the described MAO‐A activity assay is easy to implement and can readily be used to test the pathogenicity of variants in the MAOA gene in a clinical setting. Especially in this era of whole‐exome (and whole‐genome) sequencing, this functional assay fulfills a clinical need for functional confirmation of a suspected diagnosis of MAO‐A deficiency.
Collapse
Affiliation(s)
- Tessa M. A. Peters
- Department of NeurologyDonders Institute for Brain, Cognition and Behavior, Radboud University Medical CenterNijmegenThe Netherlands
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| | - Irma Lammerts van Bueren
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| | - Ben P.B.H. Geurtz
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| | - Karlien L. M. Coene
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| | - Nicole de Leeuw
- Department of Human Genetics and Donders Centre for Cognitive NeuroscienceRadboud University Medical CenterNijmegenThe Netherlands
| | - Han G. Brunner
- Department of Human Genetics and Donders Centre for Cognitive NeuroscienceRadboud University Medical CenterNijmegenThe Netherlands
- Department of Clinical GeneticsMaastricht University Medical Center+MaastrichtThe Netherlands
- Department of Genetics and Cell BiologyMaastricht University Medical Center+MaastrichtThe Netherlands
- GROW Institute for Developmental Biology and CancerMaastricht University Medical CentreMaastrichtThe Netherlands
| | - Jón J. Jónsson
- Department of Genetics and Molecular MedicineLandspitali University HospitalReykjavikIceland
- Department of Biochemistry and Molecular Biology, Faculty of MedicineUniversity of IcelandReykjavikIceland
| | - Michèl A. A. P. Willemsen
- Department of Pediatric NeurologyDonders Institute for Brain, Cognition and Behavior, Radboud University Medical CenterNijmegenThe Netherlands
| | - Ron A. Wevers
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| | - Marcel M. Verbeek
- Department of NeurologyDonders Institute for Brain, Cognition and Behavior, Radboud University Medical CenterNijmegenThe Netherlands
- Department of Laboratory Medicine, Translational Metabolic Laboratory (TML)Radboud University Medical CenterNijmegenThe Netherlands
| |
Collapse
|
3
|
Mergemeier K, Lehr M. HPLC-UV assays for evaluation of inhibitors of mono and diamine oxidases using novel phenyltetrazolylalkanamine substrates. Anal Biochem 2018; 549:29-38. [PMID: 29550344 DOI: 10.1016/j.ab.2018.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/05/2018] [Accepted: 03/12/2018] [Indexed: 10/17/2022]
Abstract
Recently, we have described an HPLC-UV assay for the evaluation of inhibitors of plasma amine oxidase (PAO) using 6-(5-phenyl-2H-tetrazol-2-yl)hexan-1-amine (4) as a new type of substrate. Now we studied, whether this compound or homologues of it can also function as substrate for related amine oxidases, namely diamine oxidase (DAO), monoamine oxidase A (MAO A) and monoamine oxidase B (MAO B). Among these substances, 4 was converted by DAO with the highest rate. The best substrate for MAO A and B was 4-(5-phenyl-2H-tetrazol-2-yl)butan-1-amine (2). To validate the new assays, the inhibition values of known enzyme inhibitors were determined and the data were compared with those obtained with the substrate benzylamine, which is often used in amine oxidase assays. For the DAO inhibitor 2-(4-phenylphenyl)acetohydrazide an about 10fold lower IC50-value against DAO was obtained when benzylamine was applied instead of 4, indicating that 4 binds to the enzyme with higher affinity than benzylamine. The IC50-values of clorgiline and selegiline against MAO A and B, respectively, also decreased (two- and 30fold) replacing 2 by benzylamine. The discrepancies largely disappeared, when the enzymes were pre-incubated with the inhibitors for 15 min. This can be explained with the covalent inhibition mechanism of the inhibitors.
Collapse
Affiliation(s)
- Kira Mergemeier
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Corrensstrasse 48, 48149 Münster, Germany
| | - Matthias Lehr
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Corrensstrasse 48, 48149 Münster, Germany.
| |
Collapse
|
4
|
Hagan CE, Schenk JO, Neumaier JF. The contribution of low-affinity transport mechanisms to serotonin clearance in synaptosomes. Synapse 2011; 65:1015-23. [PMID: 21437992 DOI: 10.1002/syn.20929] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 03/01/2011] [Indexed: 01/11/2023]
Abstract
Although many studies assert that the serotonin (5-HT) transporter (SERT) is the predominant mechanism controlling extracellular 5-HT concentrations, accumulating evidence suggests that low affinity, high capacity transport mechanisms may contribute more to 5-HT clearance than previously thought. The goal of this study was to quantify the contributions of SERT relative to other mechanisms in clearing extracellular 5-HT concentrations ranging from 50 nM to 1 μM in synaptosomes prepared from wild-type and SERT knockout mice using rotating disk electrode voltammetry. SERT inhibitors combined with decynium-22 (D-22), a blocker of several low-affinity transporters, blocked all uptake of 5-HT into synaptosomes. We found that SERT is responsible for the majority of synaptosomal uptake only at relatively low 5-HT concentrations, but comprises a diminishing proportion of 5-HT clearance when extracellular 5-HT increases above 100 nM. The effect of D-22 was similar in wild-type and SERT knockout synaptosomes. Thus, there was no evidence of upregulation of low-affinity mechanisms in knockout mice across the concentrations of 5-HT tested. These are surprising results, in light of the prevailing view that SERT is the primary uptake mechanism for extracellular 5-HT at physiological concentrations. We conclude that non-SERT mediated 5-HT uptake is substantial even at modest 5-HT concentrations. These findings, in conjunction with other studies, have important implications for understanding serotonergic disorders and may explain the variable efficacy and stability of patients' responses to antidepressants, such as the selective serotonin reuptake inhibitors.
Collapse
Affiliation(s)
- Catherine E Hagan
- Department of Comparative Medicine, University of Washington, Seattle, Washington 98195, USA.
| | | | | |
Collapse
|
5
|
Jones SR, Gainetdinov RR, Jaber M, Giros B, Wightman RM, Caron MG. Profound neuronal plasticity in response to inactivation of the dopamine transporter. Proc Natl Acad Sci U S A 1998; 95:4029-34. [PMID: 9520487 PMCID: PMC19957 DOI: 10.1073/pnas.95.7.4029] [Citation(s) in RCA: 516] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/1997] [Indexed: 02/06/2023] Open
Abstract
The dopamine transporter (DAT) plays an important role in calibrating the duration and intensity of dopamine neurotransmission in the central nervous system. We have used a strain of mice in which the gene for the DAT has been genetically deleted to identify the DAT's homeostatic role. We find that removal of the DAT dramatically prolongs the lifetime (300 times) of extracellular dopamine. Within the time frame of neurotransmission, no other processes besides diffusion can compensate for the lack of the DAT, and the absence of the DAT produces extensive adaptive changes to control dopamine neurotransmission. Despite the absence of a clearance mechanism, dopamine extracellular levels were only 5 times greater than control animals due to a 95% reduction in content and a 75% reduction in release. Paradoxically, dopamine synthesis rates are doubled despite a decrease of 90% in the levels of tyrosine hydroxylase and degradation is markedly enhanced. Thus, the DAT not only controls the duration of extracellular dopamine signals but also plays a critical role in regulating presynaptic dopamine homeostasis. It is interesting to consider that the switch to a dopamine-deficient, but functionally hyperactive, mode of neurotransmission observed in mice lacking the DAT may represent an extreme example of neuronal plasticity resulting from long-term psychostimulant abuse.
Collapse
Affiliation(s)
- S R Jones
- Howard Hughes Medical Institute Laboratories, Department of Cell Biology and Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | | | | | |
Collapse
|
6
|
Lyytinen J, Kaakkola S, Ahtila S, Tuomainen P, Teräväinen H. Simultaneous MAO-B and COMT inhibition in L-Dopa-treated patients with Parkinson's disease. Mov Disord 1997; 12:497-505. [PMID: 9251066 DOI: 10.1002/mds.870120404] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The effect of selegiline (L-deprenyl) on plasma catecholamines, clinical response, and drug tolerability was studied in 13 patients with Parkinson's disease (PD) treated with L-Dopa/benserazide and entacapone, a peripheral catechol-O-methyltransferase (COMT) inhibitor, in a placebo-controlled double-blind study. An L-Dopa test was performed on 3 study days. The first study day was with L-Dopa/benserazide only (control), the second after 14 days of treatment with 200 mg entacapone taken concomitantly with L-Dopa/benserazide in combination with either selegiline (10 mg daily) or placebo. After a 2-week washout period, selegiline and placebo treatments were switched, and the third study day was after 14 days of treatment. During the study days, clinical response was evaluated at 30-min intervals for 6 h, by using the motor score of the Unified Parkinson's Disease Rating Scale (UPDRS). In addition, repeated blood pressure measurements were made, and plasma samples were taken for analysis of L-Dopa, 3-O-methyldopa (3-OMD), dihydroxyphenyl acetic acid (DOPAC), homovanillic acid (HVA), dopamine, noradrenaline, and 3-methoxy-4-hydroxyphenylethylene glycol (MHPG). Monoamine oxidase B (MAO-B) and COMT enzyme activities were measured from platelets and erythrocytes, respectively. Entacapone improved the clinical response to L-Dopa during both selegiline and placebo (p < 0.001) treatments. The improvement was more marked during combined selegiline and entacapone treatment than with entacapone alone (p < 0.01). Entacapone significantly increased plasma L-Dopa and DOPAC levels and decreased plasma 3-OMD and MHPG levels both with selegiline and placebo. Selegiline partially inhibited the entacapone-induced increase of plasma DOPAC. Plasma dopamine and noradrenaline levels did not change. Entacapone decreased erythrocyte COMT activity by > 35% (p < 0.001), and platelet MAO-B activity was almost completely inhibited by selegiline (p < 0.001). One patient withdrew because of diarrhea, dizziness, and loss of sleep when receiving selegiline treatment. Otherwise no differences in adverse events, mean daily blood pressures, or other safety parameters were observed between selegiline and placebo treatments. Our results suggest that entacapone can be safely administered together with L-Dopa and selegiline in patients with PD, although further studies with larger number of patients and longer treatment periods are necessary to confirm this finding.
Collapse
Affiliation(s)
- J Lyytinen
- Department of Neurology, University of Helsinki, Finland
| | | | | | | | | |
Collapse
|
7
|
Lambeth DO, Muhonen WW. High-performance liquid chromatography-based assays of enzyme activities. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1994; 656:143-57. [PMID: 7952025 DOI: 10.1016/0378-4347(94)00072-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Interest in using HPLC to assay enzymatic reactions continues to grow as evidenced by the more than 100 papers published during the early 1990s. HPLC can be used for any enzymatic assay that requires separation of substrates and products before quantifying the extent of the reaction. The popularity of HPLC-based assays is due to several reasons: (1) HPLC offers unsurpassed precision, specificity, sensitivity, and reproducibility. (2) Powerful microcomputers and user-friendly software automate the running of samples and collection and processing of data. (3) Current columns, especially C18 packings, separate a very wide variety of samples, and (4) A variety of on-line detectors provide a means to detect virtually any compound. This review surveys recent papers on the development of HPLC-based assays for enzymes that degrade or otherwise modify macromolecules. Methods for assaying enzymes involved in metabolic pathways are also reviewed. Work by the authors in developing HPLC-based assays for mitochondrial enzymes that use GTP/GDP and other nucleotides that cannot be or are not easily assayed by enzyme-coupled assays is discussed. These enzymes include nucleoside diphosphate kinase, succinate thiokinase, and GTP-AMP phosphotransferase. The assays are suitable for determining the submitochondrial compartmentation of enzyme activities. Finally, current and anticipated trends in HPLC technology, including new column packings and the trend toward smaller columns that give faster separations, are reviewed in relation to enzyme assays.
Collapse
Affiliation(s)
- D O Lambeth
- Department of Biochemistry and Molecular Biology, School of Medicine, University of North Dakota, Grand Forks 58202-9001
| | | |
Collapse
|
8
|
Reyes-Parada M, Scorza MC, Silveira R, Dajas F, Cassels BK. 4-Dimethylaminophenethylamine, a sensitive, specific, electrochemically detectable monoamine oxidase-B substrate. Life Sci 1994; 54:1955-63. [PMID: 8201844 DOI: 10.1016/0024-3205(94)90130-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
4-Dimethylaminophenethylamine (DMAPEA) was characterized as an MAO substrate. This compound was unaffected by MAO-A, while its oxidation by MAO-B was linear as a function of both time and enzyme concentration, with Km = 5.8 microM and Vmax = 21.2 pmol/min/mg protein, using a crude rat brain mitochondrial suspension as source of MAO. Both DMAPEA and its oxidation product, 4-dimethylaminophenylacetic acid (DMAPAA), can be detected electrochemically at 0.85 V. The high MAO-B affinity and selectivity of DMAPEA, together with its low oxidation potential, make this molecule a unique tool to determine MAO-B activity in a wide variety of tissue preparations using HPLC-ED.
Collapse
Affiliation(s)
- M Reyes-Parada
- Cell Biology Division, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | | | | | | | | |
Collapse
|